Our Reformed fathers focused heavily on holy living. The volume of teachings they devoted to sanctification in their confessions and catechisms is striking. The Heidelberg Catechism devotes forty-four of its 129 questions and answers, more than one-third of its material, to sanctification, while the Westminster Larger Catechism devotes an impressive eighty-two of 196 questions and answers (42 percent) to this subject. By this emphasis, the Reformed churches declared that Calvinism is no mere religion of "head knowledge," and we cannot live as if it makes us the "frozen chosen," as we are sometimes derisively known. It is a religion of head and heart.
In their focus on sanctification, the Reformed churches sought to reorient the mind-set of Christians from thinking of godly living as legal to evangelical. This means that they saw obedience to God as not about guilt and legalism but as gospel-oriented. We see this in the fact that the writers of the Heidelberg and Westminster Larger catechisms placed the Ten Commandments and Lord's Prayer at the end of their respective catechisms to show us that obedience is a response to the wonder of the gospel.